Purpose: :
To evaluate contrast sensitivity (luminance and colorseparately) for people with RP implanted with the subretinalASR device (Optobionics Corp.).

Methods: :
Luminance and color contrast sensitivity testing wasperformed with 20 people with RP enrolled in the Phase II trial.As some subjects had moderate to severe vision loss that preventedaccurate testing with the Pelli–Robson chart and PV–16color test, additional tests were developed to allow testingin all subjects. Luminance contrast was determined with gratingsthat were 0.3 logMAR above the subject's threshold grating acuity.A projection system displayed contrast gratings with 0.075 logContraststeps in four possible orientations (up, down, diagonal right,or diagonal left) for a 4–alternative forced choice adaptivestaircase paradigm. Color contrast was tested with a detectiontask using PV–16 similar caps (Chow High/Low SaturationColor Test). One color cap (yellow, green, orange, blue, orred) was mixed with nine achromatic caps with a range of illuminancesaround the illuminance of the color cap. If the high saturationcolor cap was detected, then a low saturation cap with the samechromaticity was also tested. Subjects also rated their abilitiesto see different shades of grey and color in everyday objects.Subjects were assessed at baseline and then at one, two, three,four, six, and nine months post–operatively with the majorityof subjects starting testing post–operatively